


Rust, Dust & Guts

by PallanMinerva



Category: Doom (Video Games), Fate/stay night & Related Fandoms
Genre: Yeah this is violent.
Language: English
Status: Completed
Published: 2020-05-30
Updated: 2020-12-30
Packaged: 2021-03-03 03:48:57
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,711
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24448378
Author URL: https://archiveofourown.org/users/PallanMinerva/pseuds/PallanMinerva
Summary: Happy April Fool—oh shit.This was meant to be an April Fool's chapter forThe Saga of Shirou's Summons, but time passed and things got in the way and now it is aMayJune Fool's chapter instead! I may continue this at some point. This only happened because I played a lot of DOOM Eternal. Beat it on Nightmare-No-HUD, so much fun.Thanks to my Loresingers for their help. In particular I appreciateKentaKazamifor providing the original suggestion.Your ending theme is, of course,At Doom's GatebyMick Gordon.Thanks for reading.
Comments: 5
Kudos: 23
Collections: The Saga of Shirou's Summons -- Entire Collections





	1. Chapter 1

**In the first age, in the first battle, when the shadows first lengthened... one stood.**

"W-What?"

Medea stepped back in shock as she saw her arm flung across the pavilion, command seals flashing red and disappearing. Whatever she thought would come with this ritual, her summoning had produced something even the ancient witch could have never imagined

" _Another world to plunder?"_

A red maw, gaping in a screaming agony and lined with ethereal teeth, opened wide on the ground where her summoning circle had been. Someone emerged from it, a sickening old man of metal and malice, crowned in bronze and wearing a smirk that promised suffering. His eyes were filled with fire, a blaze that threatened to consume her very soul.

"W-What are you?" she asked.

" _A servant of a higher power."_

An orb of red light coalesced in his palm and she knew no more.

**He chose the path of perpetual torment.**

Kirei stopped in his tracks.

"Something is here," he spoke to his companion.

"Oho?" Gilgamesh cocked an eyebrow. "Pray tell."

He opened his mouth to reply, but the burning in his hand stopped him. He threw his holy book to the side as it caught on fire, and its flames licked at the wooden floor in hunger. The podium, the rafters, the chandelier, all soon followed and caught alight. The stained glass window shattered, imploded, and Kirei jumped back to avoid the rain of debris.

A roar, a thunder of a thousand eons, pounded in his ears, and a large muscular arm erupted from his chest. Blood spat out from his lips and agony flared around the wound, and he was thrown carelessly to the wall. The beast was an ocean of flesh, wielding two cannons that glowed a sickening yellow.

"You _dare?!"_ Gilgamesh shouted as he donned his armor with a golden flash, his gates appearing in quick succession. The beast was made quick work of, its scream neither human nor animal in nature. But the king could not rest on his laurels, for he found himself on the end of another pair of cannons, much bigger and painted in flames.

Kirei's vision began to darken as he saw the golden dust drift alongside the ashes.

**In his ravenous hatred, he found no peace.**

Rin was atop a skyscraper with Archer when the rain began.

It announced itself with the loudest crack of thunder she had ever heard in her life, something that made her shriek and cringe away. The clouded sky flashed and began to bleed. The clouds, sobbing in crimson, twisted and whirled until they screeched and tore a hole in the sky.

" _Rin!"_

A strong arm pulled her back, and Archer was in front of her instantaneously as, in a painful flash of light, _something_ appeared in front of him. Its limbs extruded out from its joints and its face was twisted into a sadistic rage. It was designed to be feared.

Two blades of light and darkness formed in Archer's hands, mirrored falchions that sliced through the limbs of the creature until it gave a dying scream and crumbled into ash. But the Servant of the Bow had no time to breathe, as the scream of his Master and the sound of a gem shattering spun him around. Another creature was shimmering with a purple veil, an outstretched claw languidly falling down to slash at her.

As soon as Archer decapitated it, the two of them were surrounded by a flood of shambling corpses and hideous demons. Rin was already at his back.

" _Archer!_ We need to—"

He scooped her into a bridal carry and jumped, tracing and breaking a phantasm to obliterate the mob behind them as they fell away. Landing was of no concern to him. The situation was.

"What the hell is going on?!" his Master shouted. "What kind of Servant could have done this?!"

_They couldn't have. This would be more like a Dead Apostle Ancestor or..._

"No," he said. "It's a Beast. It _has_ to be."

**And with boiling blood, he scoured the Umbral Plains...**

Sakura realized that something was wrong as soon as the Servant failed to appear. She could feel the growing disappointment and frustration in the glare of her grandfather ( _the thing that should not be_ ) as the project he had invested so much time and energy into failed him. The glow of the summoning circle began to fade, and his sigh gave her a momentary fleeting hope that maybe, just maybe, she wouldn't have to—

Blood that wasn't hers erupted from her mouth, the taste of sulfur and ice left on her tongue and she spat it out. She hunched over and vomited, dark crimson bile suffocating her as she tried to get rid of the foreign liquid.

_No, that's my blood, that's my blood, it's supposed to be mine it isn't foreign_

She couldn't stop, though. Her body was in rebellion against itself. Her vision pulsed in shades of red and gold, and in the corner of her eye she could see her grandfather staring, unblinking.

"Hmm..." he said as she spat once more. "A Pseudo-Servant, perhaps? Something more incompatible with you than it thought?"

A tear in reality opened behind him, a dark red portal that bathed the room in a glower of hatred. A gray muscular arm carrying a longsword emerged and impaled him, the blade drawing a straight line from his skull through his spine. Before he could let go of his mortal form, black fire encased him, and all of the worms that he was trying to dissolve into screamed as they were obliterated.

She could feel the crest worm inside of her die, and as her vision began to pulse even quicker, knew that she would soon follow.

The arm fell down as its bearer emerged; a barely humanoid thing, misshapen and unbalanced in form with large horns crowning its head. Armor clanked as it walked toward her, red eyes aglow without feeling.

It kneeled before her.

" _Maykr..."_ Its baritone rumble could have shaken the earth were it not so distorted by electronics. " _What would you have us do?"_

She stood up. No, it wasn't her, she wasn't the one who was controlling her muscles, the one who was moving her lips—

" **Establish a collection facility,"** said a voice that wasn't hers, " **and begin processing."**

**...seeking vengeance against the dark lords who had wronged him.**

Shirou's home, his refuge, was not safe.

He knew this even as he shoved his gate open and hastily tried to lock it behind him. It was pointless, of course. As he sprinted away, the demon had already phased through, its spiked jaw cackling as it trailed after him.

The reinforced pipe he had been fixing had already proved itself useless against the purple beast, but still he gripped it tightly as he turned around, trying to figure out how he could get himself out of this mess. It was all he had, but it failed him again as the creature phased behind him and punted him across his yard into his shed.

" _Agh!"_

His ribs cracked on the cement floor. It took all he could to even move aside to prevent another blow through his gut. The demon chortled, its toothy jaw flapping in amusement at his struggle. It _wanted_ him to fight just so it could make him suffer further.

Shirou stared into its triad of glowing red eyes, empty of soul and empty of thought. He had watched it tear people's limbs off and let them try to flee, only to pounce upon them as they came so close to escaping. He had watched as it expressed sheer joy from the carnage it had created, a sadistic ecstasy that only the most vile beings could relish. The only way he was able to save anyone was by drawing its attention and running.

The last time he had died, it was on his back, having killed off everything that made him human and accepting that it was his time to go.

This time, he refused to go down without a fight.

He took his pipe in hand once more, clutching it in both hands. He had nothing to say to something like this. All he could do was scream and face his death head on.

Shouting defiance, Shirou threw himself forward. The demon's arm swung forward with a heavy inevitability to punch through his chest—but before his sternum was shattered, a bright blue light flooded the room.

**And those who tasted the bite of his sword named him...**

Shirou had already fallen to the ground, clutching his eyes and covering his ears. The echo of the blast was still ringing when he faintly heard a gurgle and squelch of flesh being torn apart. After a few moments he managed to open his eyes, squinting through the black spots in his vision.

The demon had been torn in two, and the pieces of its carcass were strewn across the floor. Standing above them was a tall man, clad in green armor and carrying what looked like an entire armory's worth of weapons. The soldier turned toward him, his face barely visible through the visor, and extended a hand to him.

"T-Thank you," Shirou stuttered as he was pulled up. He could see the soldier's gaze, heavy and firm, as he took him in. The man said nothing, but held out the firearm gripped in his armored gloves. Shirou couldn't even recognize what it was, and stood frozen for a few moments until the man grew frustrated and roughly shoved the gun into his chest.

"W-what?"

He received no verbal response; instead, the soldier threw a small carton at him. He was aware enough to grab it out of the air. His eyes widened as he opened it and found it full of shotgun shells.

_What... did he just give me a shotgun?_

Shirou quickly looked up as furious howls tore through his yard. The soldier pulled out an even larger firearm, thick, gray, and blocky. Before Shirou even realized that more demons were streaming into his yard, the soldier was dispatching them with ease. Their bodies were shredded by a rain of lead, and when they lunged forward, a long blade extended from his arm to tear into them.

The blood and entrails that decorated his grass made him sick, but he barely managed to hold it back. As the last demon fell to one final bullet to the head, the soldier looked back at him, his rifle held lazily at his side. Behind him, Shirou could see plumes of smoke billowing from all across the city. No longer fearing for his life, he raised his head to the clouded sky, the crimson drizzle, and the screams. The echoing screams of dying people begging for their lives the _smoke the fire the numbness encroaching on his soul_

The flashback faded as the gun in his hands was ripped from his grip. The soldier had taken it in one hand, and with a single smooth vertical motion, loudly cocked it. He flicked his head backwards.

" _Your city is facing imminent destruction."_ A voice projected out from the suit of armor, but he couldn't see the soldier's mouth move, and the tone did not match him at all. " _The Slayer is tethered to your world through the seals on your hand and already has a plan to neutralize the demonic threat. He is offering you the chance to fight and to save your people."_

He spoke before he even had a chance to think.

"Yes."

The man nodded and threw the shotgun at him. This time, Shirou caught it.

" _The nearby park has a newly grown Gore Nest,"_ the electronic voice said. " _My models are indicating that eliminating it will prevent losses upwards of 47% in the neighborhood."_

The unfamiliar fire of hatred flickered in his chest, and instinctively he tried to quench it. But at the heart of the flame was the memory of Ayako being torn to pieces. He clenched his jaw. He didn't need any other justification. There was no mercy, no saving these _things_. They needed to die.

The soldier strode out of the property. Shirou's grip on the gun tightened and he hurried after the man—no. This soldier was more than a man. No name could capture what he was. Yet Shirou could feel his identity engraved into his bones, see his title in the sunlike aura that shone off his armor. The Hellwalker, the Unchained Predator, The Feared One...

**The Doom Slayer.**

**Notes for the Chapter:**

> Happy April Fool—oh shit.
> 
> This was meant to be an April Fool's chapter for _The Saga of Shirou's Summons_ , but time passed and things got in the way and now it is a ~~May~~ June Fool's chapter instead! I may continue this at some point. This only happened because I played a lot of DOOM Eternal. Beat it on Nightmare-No-HUD, so much fun.
> 
> Thanks to my Loresingers for their help. In particular I appreciate **KentaKazami** for providing the original suggestion.
> 
> Your ending theme is, of course, [_At Doom's Gate_](https://www.youtube.com/watch?v=Jly9qp40rfw) by **Mick Gordon**.
> 
> Thanks for reading.


	2. Up for Adoption & Chapter 2 draft

**Notes for the Chapter:**

> Hello there. I would like to say it’s good to see you, but I come bearing only bad news. I’m putting this story up for adoption. I had already begun overwhelming myself with a lot of other story ideas by the time this had come out and to this day I am still somewhat paralyzed. I would like to get it off of my plate so that I can focus my energy on writing my other fics.
> 
> At the very least, I can give you what I wrote already for the second chapter. Note this is unpolished, unworked on by any of my friends. I give it to you in the hopes you can do something interesting with it. You don’t have to ask me for permission, just give it your best shot. Any number of people can take this, I will not officially sponsor or endorse any stories taking up this mantle.

Two knocks on his door, soon followed by a third.

"Ani-ue," Reines called out, "are you busy?"

"Yes," was the quick reply she received. She looked back at Gray, whose eyes were anxious at the thought of disturbing her sensei, but shrugged and opened the door anyway.

"Well, you can't be that—"

"Reines, shut up or get out." His tone was so pointed that she wouldn't be surprised if he started growing spikes. He still hadn't looked at her, staring intently at the TV.

"Testy today, aren't we?" she said quietly, moving away from the door to allow Gray to hesitantly enter.

"Be _quiet."_

She turned her attention to his television as well, noting that it had been tuned to BBC News, currently displaying a pair of male and female anchors.

" _Our Top Story of today: last night, Japanese Prime Minister Junichiro Koizumi along with the entire National Diet was killed in what is being described as a freak terrorist incident that has shut down the island nation. We go now to our Asian correspondent, Dean Gallard, in Shanghai. Dean, what've you got for us?"_

The image switched to a young man, brown-haired and worry painted in his green eyes, though he tried to hide it with his stern expression.

" _Not much, I'm afraid. The Japanese ambassador has locked himself in his compound here in the capital, and notice has been sent out to all Japanese citizens abroad to extend their stay out of the country as long as they can."_

"Last night," her adopted older brother said as the man continued to talk, "really yesterday afternoon, one of my contacts in the Orient sent me the following information."

He held out a printed letter to her that she took without word.

_Veil torn. Send help._

"Veil...?" Gray asked.

"Something happened that broke the secret of magecraft," Waver said. "Something that has apparently crippled the government and closed the country off. I was already aware that the Holy Grail War was supposed to start early this year, but—"

He stopped as a crack of thunder rang out so loudly that his TV speakers strained and crackled.

" _W-What?"_ The young reporter could not hold his shock back any longer as the sky turned red and cloudy. All the sunlight of the day was washed away as a thunderstorm of enormous proportions coalesced from nothing, and lightning rained from the sky, shattering the windows of every glass tower in sight.

Gray gasped as a bloody monster appeared out of thin air, causing both the cameraman and reporter to scream. The camera was quickly thrown to the ground as its holder began to sprint away, but it landed at the perfect angle to watch as the reporter was speared through the heart with a lanky, three-clawed hand. His death gurgle was cut off as the image quickly transitioned back to the news anchors, whose expressions were equally pale.

" _We'll..."_ The female anchor hesitated, swallowing. " _We'll be right back."_

The clack of a lock being closed echoed in the silence, and Reines turned to see her brother closing a briefcase.

"Shishou, where are you going?" Gray asked before she could.

"Rome," he said, pulling out a cigarette from his desk drawer and lighting it. "I'll be negotiating with my contacts in the Church."

He turned to exhale away from them.

"I have a feeling that whatever this is, it will not be stopping at the East."

**[GREATER THAN FEAR]**

Shirou heaved, leaning on the empty barrel of the shotgun. Nothing was left in his stomach by now, so all he tasted was bile and spit, but he had to try anyway. An intestinal mass speared out of the earth before him, straight through old man Masamune's electronics store, and surrounding it was at least two and a half dozen bodies, their innards strewn about like dinners that toddlers had played with. Some had been there when the two of them had arrived, but others had fallen by his hand.

His white shirt had long since been painted red and yellow, and his skin was caked in blood and entrails. The constant sense of disgust haunted him for hours now.

He hadn't been prepared to kill, but it was kill or be killed, and the Slayer made a good argument for killing.

The soldier tore through their foes like wet papyrus, an unstoppable machine that both input and output violence. He was diligent in his destruction, and yet somehow he always left a few of the shambling zombies around for Shirou to practice his aim on. He would dig up boxes of ammunition in between the viscera and rubble, seeming to conjure them from nothing, and every other case of shotgun shells he found he would throw to Shirou. Small kindnesses that Shirou never would have expected from the imposing soldier kept coming.

" _The local Gore Nest is now cleared,"_ said Vega, the Slayer's AI. " _I will mark a path on your HUD that will take you to the nearest proto-Hive."_

"Wait, hold on—" Shirou coughed violently, but managed to speak. "Can we—can we please take a second to rest?"

The Slayer turned to look at him, or at least Shirou _thought_ he did, and after a few moments he nodded and walked to a pile of rubble that was marginally less stained than any other nearby pile. As Shirou followed him, he sat down and pulled a sawed-off double-barreled shotgun from his hip, cleaning it with a grimy rag he dragged out of the rubble.

Shirou fell down beside him with a grunt, putting the shotgun to his side (barrel facing _away,_ he had learned his lesson) and leaning back on his arms. The red sky was continuing to darken as what last amount of natural sunlight slowly faded over the horizon, replaced instead by an ominous glow that cracked with every peal of thunder. He could still hear—

_the screams the begging the crying the tears_

_pleading for rescue pleading for saving_

_please let me live let me live I don't wanna die I don't wanna die_

Shirou bit his tongue, forcing the flashback away with the taste of iron pain. Every plume of smoke on the horizon was a fog of memory that he had to fight through, and only terror and adrenaline proved to be strong barriers against it. He shook his head, throwing the last pieces of the nightmare away, and focused on his breathing until he started to relax.

"Vega," he said, "how far have they gotten now?"

A pause.

" _Recent satellite imagery shows that 17% of the downtown district has been razed,"_ the AI said. " _A further 29% has been heavily damaged, with at least two skyscrapers having collapsed. There have been no official estimates of lives lost yet, but reports indicate that simultaneous demonic invasions are commencing in neighboring countries. At the current growth rate, Japan will fall within the week."_

Shirou let out a shuddering breath. He was still trying to get a handle on the situation, and here it was escalating even further beyond his grasp.

"What are we going to do?" he asked.

" _The Slayer believes that, as the first location of the outbreak, the source must be in the vicinity of this metropolitan. He will be searching for connections to it as we destroy more Gore Nests. You are welcome to accompany him."_

"Of course!" Shirou couldn't stop now. Not when he was given the chance to _do something_ with his life. Something immediate and concrete, that he could physically see the results of. He _would_ help save his home.

The sound of rubble falling had him turning his head up, but the Slayer had gotten up even faster and pointed his gun toward the sound.

"...can't _believe_ this stupid Grail War. First it was early, then I got Archer, and now freaking _demons_ are invading."

He knew that voice.

"Actual, goddamn, interdimensional demons," said Rin Tohsaka from what must have been just a block down the street. He strained to look around the Slayer's legs. She was accompanied by a tall man dressed in black with a red overcoat, and instantly Shirou felt in his gut that this man was anathema to him. "What's next? Super AIDS?"

"Rin," the tall man said, "stop it. We still haven't fully gotten over SARS yet."

"How the hell do you know that?" She spun around to face him. "There's no way the Grail told you that."

"I—uh—I mean—look over there!" The man pointed over in their direction.

"Stop trying to distract—huh?" Rin finally noticed the two of them. "Who the—Archer, is that a freaking Servant?"

"Doesn't look like any kind of Servant I've seen..." the man said. "Wait a second..."

His face grew dark as he spotted Shirou.

"Oh, of course _you're_ here." He crossed his arms.

"Emiya...?" Rin said, and Shirou gave her a hesitant wave, trying to smile even though he really wanted to punch that asshole in the face.

"Hi, Tohsaka."

"What the f—are you okay?!"

"Yeah, why?"

" _Have you looked in a mirror lately?!"_

He felt a wave of nausea come unbidden. "Thanks, I was trying not to think about that."

"Oh, uh, sorry." She fidgeted for only a moment. "No, hold the fuuuuront door, what are you doing here?!"

**[GREATER THAN HATE]**

Sakura wanted to scream.

Sakura wanted to cry.

Sakura wanted to run away.

Sakura wanted to die.

As she watched the lines of hundreds of people shamble through the _collection facility_ (a barely-hidden euphemism that could have induced nausea in her), she begged for any deity that could hear her to end this nightmare.

**Notes for the Chapter:**

> The chapter was originally meant to be titled “Paradise Lost” after the song on the DOOM Eternal soundtrack, so I suppose that’s your ending theme.
> 
> Again, thanks for reading.


End file.
